Testing system



Nov. l1, 1930. H. w. oNElLl.

TESTING SYSTEM 2 Sheets-Sheet l Filed May 25, 1929 glmfllll-lh #W5/vpna H W UNE/LL mw Sv Arm/wey Nov. 1lz 1930. H. w. oNElLl.

TESTING SYSTEM Filed May 25, 1929 2 Sheets-Sheet 2 Nimm Patented Nov. 11, 193() ystars. Parnu-r; rricl naar HENRY W. OITEILL, OF ELMI-I'URST, NEW YORK, ASSIGNOR TO BEL.' TELEPHONE-LABO- RATOBIES, INCORPORATED, OF NEW YORK,' N. Y., A CORPORATION OF ITEW YORK TESTING SYSLEIVI` 4Application filed May 25, 1929. Serial No.w365,913.

This invention relates to a transmission measuring or testing system and more particularly to a trunking arrangement for such systems whereby lines, appearing at a switch- 5 board, may be extended to a point distant from the switchboard` where ,facilities are provided for testing or measuring 'the transmission characteristics of the lines.

An object of the invention isto facilitate testing of telephoner lines whereby transmisn sion faults may be readilyand quickly`identified. Y, y l.

A feature ofthe invention resides in means associated with a plurality of trunk circuits running-between a toll switchboard and-the testing point, and controlled from'the testing end, whereby all toll lines extended-tothe testing point over said trunks are conditioned for conversation'and indicated as busy in the usual manner `as long as the testing equipment is connected to any one of said trunks and, conversely, are all restored to normal and indicated as idle as soon as the testing equipment is disconnected therefrom.

Another feature of the invention resides in means associated with said trunk circuits whereby exclusion of transmission loss pads, normally included inthe lines under test, may he controlled from the testing equipment.

. A further feature ofthe invention resides in an improved relay arrangement for'talking trunk circuits, running between said aline signal is displayed at the testing end of the trunk when the line is seized at the switchboard and whereby supervisory 4signals are transmitted in the opposite direc- 40 tion. l

The features of the invention'will appear from the following description and the accompanying drawing in which:

` Fig. l represents a group of three transr mission testing trunk circuits SMTl, SMT2 and SMT3 adapted to connect any three of the sleeve supervision toll lines SL1, SL2, SLS and SLi, terminating at the toll operators positionl T01 with transmission testing `equipment indicated asTTB. A talking be-vt'raced from battery switchboard and the testing point, wherebyv trunk circuit STTis also shown which provides facilities whereby the toll operator can signal and talk with the transmission test man.' I

Fig. 2 represents a similar group ofthree trunks forconnecting bridge supervisiontoll linesBL1, etc., with the-same or like testing equipment. A talking trunk BTT similar in character to STT but adapted to function withy thevoperators cord circuits at position T02 isalso shown.

The invention'will be best understood by describing the' connection of'three toll lines to the testing equipmentTTB and it will` i ant atthe transmissiontesting point, to,4 be

hereinafterreferred Vto as fthe test man, requests the toll operator at position T01, over an instruction circuit not shown,'to connect transmission measuring trunks SMTl, SMT2, SMT3, with the toll lines inquestion by inserting plugsll, 2 and 3 into toll line jacks.

.4, 5 and 6. l When plug 1,' for example, is inserted in jack 4, a simpleiz circuit for operating re-y l lay 42 inthe toll line is completed which can over parallel paths including resistances 43and 44, upper lower'normal contacts of relay 16, the tip andring of thetrrnkI and toll line, impedance's 45 and 46, and lwinding` o'f-rel-ay 42'gto ground. ,Relay 42 'inlopera-ting opens th circuit of relay 47, therebyl preventing 'it operation when relay 22 operates which' wil.' belater described, l y

' This connection,` however, unlike the con'- nection of an ordinaryoperators cord circuit or trunk, has no busying effect on the convnected toll line, at this time, dueto trie fact that the sleeves of plugs l, 2 and 3 are normally free from battery potential and are grounded at back contacts of relay 7. The seized toll lines therefore continue in normal service and may be taken-for use at any position at which they are inultipled until such a time as the test man is ready'to take Vcontrol f Vof them. When the test man is ready to make thedes'ired tests, he will insert one or more of the-'double plugs 8, 9 andV 10, associated with theV testing equipmentgrinto the corre#Y sponding double trunk jacks 11,* 12 yand 13 I whereupon relay 14 Operates frombattery atv theitestboard TTB ov-erfoneor more of the 6, and'ZOla-nd consequently remain inert, Y

v cuits, but relays obviousY sleeve circuits shown. One circuit'- maybe'traced from battery, contacts of key 52, resistances 15a and 15", sleeve contacts vof plug 8 and jack 11, winding of vmarginal relay 16 and righthand windingof relay 14'to ground., Another circuit canbe traced from battery,

marginalrelay 19, and middle winding of 'relayi1'4 to ground and a third circuit can be ltraced frombattery, resistance 20, sleevecon- Vtacfts ofvrjackl() and'plug 13, marginal relay f 121 and left-hand'winding of relay v14 to ground.I Y f Relay1`4 operates in oneorall ofthese cir-v 16, 19 andv 21 being marginal wil-l vnot operate incircuit with their respective series-resistancesla and 2;, 17aand ly The/,operation of relay 14completes an ob.-y

- Vwhich energizes v Vlay 24operatesrelay 29 Vwhich energizes busyA ings is shown, three single relayscan obviousv be used-tofaccomplish,the same result.

in operatingiremoves and 24. v obvious 'circuit for relay 25 which in turnfop` crates busy signal 26and all other busysignals V'asso viated Vwith line SLlv at itsinultiple appearances. Relay y23 operates relayf Y27 'busy signals 28, etc., andaresignals 30, etc.

Operation of relay* 25 `also opens the nor` fmally closed impedance j bridge, including condenser 3.1 and'resistance 32, acrossithe line d SU thereby Condntning wenn@ repairing,

Opel'ltlOll also Open lar impedance bridges normally across lines SLZTandYSIs respectively. A Y.

-Thetoll lines connected to Vthef'jesting'fp equipment `arenow indicatedas busy the test man can listen in, by means of telephone equipment'associated-withthe test boardbut` not shown,- and when'the line'sbecorne vidle he may proceed with the desired tests.

and the equipment for making these tests, is

attempted in this application as such method and equipment Vform n0-part .of the present invention. f Y y Interposed in `the lines Y Sli, etc, are

are known as trafnsmissionloss pads for `key" 52,"re`sistances V17r and 17?), sleeve [contacts of plug 9l and jack 12,

erating Y ainces 3 3 ,any other similar dline sistance and shunt capacity.

The pad for line SL1 is indicated by series resistances`-33, 34, 35and 36, and the shunt capacitybyv condenser.37..v Similar pads are 'interposed in the .other lines, and.

SL?. j .Y

Under certain conditions it may be desired to reiiderthese loss pads ineffective-and there? fore each pad has an associated control relay 38, 39, 40 and 41, respectively, which isi shunt and short-circuit the series resistances.

VThese pads and similar relay controlmeans are shown in the copending application iled controlling transmission over the lines. Y -Thesetra`nsmission pads consist of Vseries rei.

, adapted, when operated, to open thecapacity by Glezen .v et al., SeriaLiNo. 291,6 82`,'v filed July 10, 1928. 1

In case the test man' desires to efectively remove the pad from t oll,line` SL1, for eX! ample, he will operatekey 18 associated with the testboard TTB', thereby sho'rt-circuiting resistance 15b, whereupon marginall relay 16 operates in seriesy with the rightehand winding of relay 14. yRelay 16in operating. opens at its upper and lower contacts the s implex"7 L circuit .previously described, lwhereupon relay 42 releases, thereby closing the circuit for oprelay 47--which wasv prepared vwhen l. jY

relay 22 operated;

Relay'47 V-n operating completes 'an' obvious i Y circuit for operating relay 38 which in oper-,V l.

'ating opens latits contacts '48 a capacity shunt'Y across thev toll line,;wliich includes condenser .Y

37 and closes its contactsv r 49 .and 50,r thereby v placing. sliortlcircuitsaround the series resist-- and 34, and35 and'36 respectively. Y Release of'key `18 increases the resistance. of thecircuit of relaylG whichy thereupon re# leases, which causes relay 42 to againoperate. Operation ofrelay; 42'release's relay 47 `which,`

inturn releases. relay V38 which removesthe f.

short-circuitffrom the line'resistances 33,l 34,

ifaiid 36 and -reconnectsjthe capacity shunt: i

across the line.

VOperation of key'olin a like manner effec'-r :tively removes'theloss pad fromY line SLZV or.

with which the plugf9 may associatedf In the'pre'sent circ uit arrangement, itisnot.y j

Vconsidered necessary to remove the'padfrom l f the functions of the testing equipment associated with plug 10. It therefore needs no furtherexplanation. Itis obvious, however,

v Y :that pad control could be provided by vadding No'. description of the method of testing,

'i In case the testman desires to testtlietrans-r 'missien through one 'of the toll. operators" :the linev (SIF) 'which mayybeassociated with lug y10. jThe reason 'for `this has to d oV with the method of making the ,desired tests, and' Y.

cord circuits 53 he can instruct Vthe operator to' plug one end of theV desired cord into patch`l ing'jack 54-vand the other endinto Vpatching i associated Withline BL? -vvouldbe electively: removed,.-i1i a similar manner, by operating the itest nian to measure the transmission characteristics of any cord circuit at position- Y KTO.2 suoli ias ycord-circuit 92, Vfor example,

1 0 functions' cord. circuits.,

- ThetalkingtrunkTT of Fig, 2 ina similar manner to STT'ofFi 1. When the toll operator inserts a plug, o one'of her suclias 92, into jack :98, line relay 94-.op'erates' invarircuitffroni battery (not shown) onthe'sleeveotthe-cord cir-V .cuitf92,- k'contacts 952er" relay v96, contacts 97 Y ofrelay 98 andvvinding of relay 94to'ground.

. opens the vloatterybridge l normally y standing Relay 9a-,operates i and closes an obviousl circuit ,toy light-,the line lamp 9 9 at the test board. When the testvmananswersloy insertingplug l0 into the double jack 100, sleeverelay 96 Voperates from battery. .associated With the across ythe trunkfand also opens the short;

circuit-*aroundi-relayYV 98 by breaking con-j' jicloses yits contacts 101,

thereby@sliortcircuitingf relay 941 which i. thereupon! releasesfto extinguislilinellamp l' 3 stitutediior-the Winding off relay 94;, Whicliis 99. :The: Winding of -rel'ayg98i is now suhshort-cirCllt'ed. R lay .f 98 operates in the 1 previouslymentioned sleeve circuit; and locks i itself .operated, andrelay '94" sliort-circuited, 2.3551

cuit.

under control ofthe vtoll operato-rs cord cir-` v inztheaiseft'f rig. agiata .toiifc'ofra'circia Y Y 92 Adi-lersirom cord circuit` 5 6 yof Fig. `1 in l vthat the vcord supervisory rsignal iscontrolled by al supervisory relay in series vvitli oneof the talking conductors(ring)l of the; cord conductor asin the case swered, ythe Vsupervisory :relay operated o from overcontacts o relay 96,

cord circuit-,j VOper-ation ot relay `,96 l removed this-battery bri lgeand caused the release'of 1 'guished the supervisory signale i.

L. ;A ii. will lbe nagaan-g Connection. Withffbeai that ftheV line relaysffvr of Fig. 1' andf9/lA of Fig.' f2 are'fbotli controlled; in ltheir operation Yl yandreleasefby'the removal or connection of i a shunt. l'around their-windings, .there being no seriescoIitaQtsinVolVed, which under certain conditions Vmiglit:cause irregular .opera-y tion of therelays vin question.v

What is claimed is:

l. In a transmiss'on: measuring system, a

i plurality for each line, a plurality of groups of trunks, f leach formed. from g a; plurality y, ot `in dividual v of'lines tobe tested, a busy signal wem a testing circuit includingv transmission meas- Huring; mea ns, means for connecting.V said testing circuit with the other end of any one` of said trunks, and means automatically respon-v; sive to suchcoiin'ection toactuat`e the busy 'Signals associated With allof Vtlielines kcon.. nected tosaidtrunks.'`

2. Ina transmission measuringsystem, a. v'plurality of lines to be tested, each lineV com -v prising means for conditioning the line" for conversation, aV plurality of' groups of trunks,

leach formedfroni a plurality'of individual trunks, means for connecting any one ofV the trunks, ymeansfor connecting any `one of the:V Y f lines With one endy of anyone of' the' trunks,

lines with one end of .any rone of the trunks,

a testinglcirc'uit including transmission meas# uring means,` means for 'connecting said test-1V 3211i a vtransmission 'measuring system, fa

pluralityV of `lines lto be' tested, respectively associated 'means said `lines forconversation, ajbusyfsignal'ior each line, a plurality of groups of trunks, each means for connecting any one ofthe lines Withlone end'ot 'any oneoff the 'tr'unl s,' fa testing circuit yincluding,transmissionV measf uri-ng means, means forY connectin@ jsaiditest-V ing circuit Witli'the other end of said trunksand means automatically responsive i to suoli ingcircuit With the other end of any one of" lsaid trunks, and means automatically respon sive to such connection to act'uate the'condi# VVtioning means associated With'all of the lines v.connected to said trunks.A f

forconditioningeach of formed romaplurality of vindividual trunks,v 9.5

connection to actuate said conditioning means :lines connectedyto said trunks.

4." a transmission measuring system, a urality ofV lines to be tested having transmission loss padsnormally include'd'therein, Va lpluralityof groups of trunks, eachfformed `tro/ m aplurality of individualtrunks, means for connecting any one of the lines' with lone l v11o including ltransmission "measuring means,

endoffany one ofthe trunks,"a testingcircuit means for connecting said test'ing'circuitwith to display andmeans in said trunk circuits controlled Signals associated ,with .au of a@ i 'theotherendotany one otsaid trunks, means i; automatically responsive to such Vconnection ythe lousy .signals associated with from'said'testing, circuit for-causing .the eX- z clusion'of said transmission. loss pads from anyof the respectively Vassociated lines.

5. In a signaling system, a line, firstand second relays connected in series Withjsaid line, a sourceof current adapted yto loe` con- Y Y l nected to vsaid line to energizel said second relay, a signal'controlled by said Vsecond relay,

a ythird relay, Vcontact means associated with saidyfirst and thirdrelays normally cooperan f ving `to short-circuit said first relay, a second source of current, operator controlled means for connecting said second source ofcurrent 1 15V allfof thelines' connected-With said 'trunks to said third relay to cause its operation to open the short circuit around the rst relay and permit its operation, and other Contact means associated With said rst relay responsive to its operation to short-circuit said second relay.

In Witness whereof, I hereunto subscribe my name this 23d day of May, 1929.

HENRY W. ONEILL. 

